This SCR timer was found in an old English documentation. The SCR can be the TUIC106 and modern equivalent transistors like the BC557 for TR1 and BC547 for the others.
This circuit can handle 25 A unde a 32 V voltage using a hight power old transistor. This...
We found this circuit in a 1980s publication on telephony. The circuit uses an integrated...
The frequency of the square signal produced by this circuit depends on the light falling onto the...